Agrochemical formulation

ABSTRACT

A suspoemulsion formulation comprising: (a) a continuous phase comprising: (i) one or more block co-polymers, and (ii) one or more non-ionic surfactants; (b) a dispersed emulsion phase comprising: (i) a chloroacetamide, and (ii) a polymeric stabiliser; and (c) a dispersed solid phase comprising: (i) a 2-(substituted benzoyl)-1,3-cyclohexanedione herbicide; and (ii) a stabilising metal salt.

The present invention relates to a novel agrochemical formulationcomprising at least two active ingredients and the use thereof.

Agricultural pesticide manufacturers have identified the need forbroad-spectrum pesticidal products. Single active ingredientformulations rarely meet such broad-spectrum requirements, and thuscombination products, perhaps containing up to four complementarybiologically active ingredients, have been developed. Such products haveseveral additional advantages e.g. elimination of tank mixing; reductionin inventory products; saving in time and money, and a reduction in thenumber of times the crop is sprayed.

The development of such products is relatively simple providing that theactive ingredients to be combined are physically, chemically andbiologically compatible. In these situations the active ingredients canbe combined in a broad range of formulation types well known in the art.Where the active ingredients are not physically, chemically and/orbiologically compatible, it has been necessary to develop novelformulations to overcome the problems associated with suchincompatibilities. One example of a formulation type is the so-called‘suspoemulsion’ formulation. These suspoemulsion formulations are formedby combining an emulsion phase, containing one or more activeingredients, with a continuous phase also containing one or more activeingredients in the form of a solid dispersion. This type of formulationhas several user advantages related to ease of transportation, storageand field application.

However, the formation of such suspoemulsion formulations is rarelystraightforward. The technical challenge and complexity to formulatesuspoemulsion formulations with satisfactory physical and chemicalstability has been previously reported (e.g. Suspoemulsion Technologyand Trends, Joseph R. Winkle, Pesticide Formulation and AdjuvantTechnology, CRC Press, 1996).

Particular problems were encountered when attempting to formulate theactive ingredients of the present invention into a suspoemulsion. One ofthe preferred active ingredients used is mesotrione(2-(2′-nitro-4′-methylsulphonylbenzoyl)-1,3-cyclohexanedione), which maybe present either as the free acid, or as a metal salt. Mesotrione freeacid is chemically unstable in aqueous medium under a range of pHconditions and/or concentration. The problem of the chemical instabilitymay be overcome by chelating the mesotrione free acid with a metalchelating agent, for example a copper or zinc salt. However, theintroduction of the metal salt into the composition surprisingly led tosevere complications with the physical stability of the resultingsuspoemulsion. It was noted that the chelated mesotrione particles weremigrating into the emulsion phase—a phenomenon known asheteroflocculation/coagulation. Depending on the surfactant system, thisheteroflocculation/coagulation could happen instantaneously on amacroscopic scale or very slowly, only under stress at a microscopicscale. This was considered very abnormal behaviour as it appeared thatthe event was not just a flocculation (surface to surface) event, butrather an actual migration of the mesotrione to the inside of theemulsion droplet.

It is therefore an object of the present invention to provide achemically and physically stable suspoemulsion formulation thatcomprises a 2-(substituted benzoyl)-1,3-cyclohexanedione herbicide asone of the active ingredients.

Accordingly, a first aspect of the invention provides a suspoemulsionformulation comprising:

(a) a continuous phase comprising

-   -   (i) one or more block co-polymers, and    -   (ii) one or more non-ionic surfactants;

(b) a dispersed emulsion phase comprising

-   -   (i) a chloroacetamide, and    -   (ii) a polymeric stabiliser; and

(c) a dispersed solid phase comprising

-   -   (i) a 2-(substituted benzoyl)-1,3-cyclohexanedione herbicide;        and    -   (ii) a stabilising metal salt.

The suspoemulsion formulation of the present invention may optionallyfurther comprise one or more additional active ingredients. The one ormore additional active ingredients may be a pesticide, for example aherbicide, fungicide, insecticide or the like; or the additional activeingredient may be a compound selected from the class of compounds knownas safeners or antidotes. The concentration of additional activeingredient in the formulation is suitably in the range of from 1 g/l to500 g/l, and preferably from 2 g/l to 300 g/l.

In one preferred embodiment, the suspoemulsion formulation furthercomprises an additional active ingredient which is a herbicide, forexample a herbicide selected from the class known as triazines, forexample atrazine or terbuthylazine; a phosphonate herbicide, for exampleglyphosate or salts thereof; or a phosphinate herbicide, such asglufosinate or salts thereof. The concentration of additional herbicideis suitably in the range of from 5 g/l to 500 g/l, and preferably from10 g/l to 300 g/l. Most preferably, the additional herbicide is atriazine, preferably atrazine or terbuthylazine. Suitably, theadditional herbicide is present in the dispersed solid phase of thesuspoemulsion.

In a second preferred embodiment, the suspoemulsion formulation furthercomprises an additional active ingredient selected from the class ofcompounds known as safeners or antidotes, for example benoxacor. Theconcentration of safener is suitably in the range of from 1 μl to 100μl, and preferably from 2 μl to 40 g/l. Suitably, the safener is presentin the dispersed emulsion phase of the suspoemulsion.

In a third preferred embodiment, the suspoemulsion formulation furthercomprises at least two additional active ingredients, wherein at leastone of the additional active ingredients is a herbicide, for example atriazine, such as atrazine or terbuthylazine, and at least one of theother additional active ingredients is a safener, for example benoxacor.

The continuous phase may be any suitable solvent, for example water,glycol or alcohol, but is preferably water.

Examples of suitable block copolymers that may be used in the presentinvention (in either the dispersed solid phase or the dispersed emulsionphase) include alkyleneoxide copolymers (such as ethyleneoxide-propylene oxide block copolymers, ethylene oxide-butylene oxideblock copolymers), C₂₋₆ alkyl adducts of ethylene oxide-propylene oxideblock copolymers, C₂₋₆ alkyl adducts of ethylene oxide-butylene oxideblock copolymers, polyoxyethylene-polyoxypropylene monoalkylethers suchas butyl ether, methyl ether, propyl ether, ethyl ether, or mixturesthereof. Additional examples of block copolymers and their availabilitywill be well known to those in the art. Suitably, the concentration ofblock copolymer in the suspoemulsion formulation of the invention isfrom 0.1 to 10.0%, and preferably from 0.2 to 7.0%.

Examples of non-ionic surfactants that may be used in the presentinvention will be known to those skilled in the art, and include but artnot limited to EO-PO block copolymers, butoxy block copolymes, graftcomb polymers, polyethylene glycol mono and diesters, polyglycerylalcohol ethers, alkyl ethoxylates, tristyryl ethoxylates, alkyl arylethoxylates and alkylpolyglycosides. Suitably, the concentration ofnon-ionic surfactant in the suspoemulsion formulation of the inventionis from 0.2 to 15.0%, and preferably from 0.5 to 10.0%.

Examples of the chloroacetamide suitable for use in the presentinvention include compounds of formula (I)

wherein R¹ is hydrogen, methyl or ethyl; R² is hydrogen or ethyl; R³ ishydrogen or methyl; and R⁴ is methyl, methoxy, methoxymethyl, ethoxy, orbutoxy. Suitably, the chloroacetamide is selected from the groupconsisting of metolachlor, acetochlor and alachlor, preferablymetolachlor, and most preferably, s-metolachlor. Suitably, theconcentration of chloroacetamide in the suspoemulsion formulation isfrom 100 to 750 g/l, more suitably from 250 to 500 g/l.

Examples of suitable polymeric stabilizers that may be used in thepresent invention have a molecular weight between 10,000 and 1,000,000daltons and include, but are not limited to polypropylene,polyisobutylene, polyisoprene, copolymers of monoolefins and diolefins,polyacrylates, polystyrene, polyvinyl acetate, polyurethanes orpolyamides. Suitably, the concentration of polymeric stabilizer in thesuspoemulsion formulation of the invention is from 0.1 to 7.0%, andpreferably from 0.2 to 4.0%.

Suitably, the 2-(substituted benzoyl)-1,3-cyclohexanedione for use inthe present invention is a compound of formula (II)

wherein X represents a halogen atom; a straight- or branched-chain alkylor alkoxy group containing up to six carbon atoms which is optionallysubstituted by one or more groups —OR⁵ or one or more halogen atoms; ora group selected from nitro, cyano, —CO₂R⁶, —S(O)_(m)R⁵, —O(CH₂)_(r)OR⁵,—COR⁶, —NR⁶R⁷, —SO₂NR⁶R⁷, —CONR⁶R⁷, —CSNR⁶R⁷ and —OSO₂R⁸;

R⁵ represents a straight- or branched-chain alkyl group containing up tosix carbon atoms which is optionally substituted by one or more halogenatoms;

R⁶ and R⁷ each independently represents a hydrogen atom; or a straight-or branched-chain alkyl group containing up to six carbon atoms which isoptionally substituted by one or more halogen atoms;

R⁸ represents a straight- or branched-chain alkyl, alkenyl or alkynylgroup containing up to six carbon atoms optionally substituted by one ormore halogen atoms; or a cycloalkyl group containing from three to sixcarbon atoms;

each Z independently represents halo, nitro, cyano, S(O)_(m)R⁹,OS(O)_(m)R⁹, C₁₋₆ alkyl, C₁₋₆ alkoxy, C₁₋₆ haloalkyl, C₁₋₆ haloalkoxy,carboxy, C₁₋₆ alkylcarbonyloxy, C₁₋₆ alkoxycarbonyl, C₁₋₆ alkylcarbonyl,amino, C₁₋₆ alkylamino, C₁₋₆ dialkylamino having independently thestated number of carbon atoms in each alkyl group, C₁₋₆alkylcarbonylamino, C₁₋₆ alkoxycarbonylamino, C₁₋₆alkylaminocarbonylamino, C₁₋₆ dialkylaminocarbonylamino havingindependently the stated number of carbon atoms in each alkyl group,C₁₋₆ alkoxycarbonyloxy, C₁₋₆ alkylaminocarbonyloxy, C₁₋₆dialkylcarbonyloxy, phenylcarbonyl, substituted phenylcarbonyl,phenylcarbonyloxy, substituted phenylcarbonyloxy, phenylcarbonylamino,substituted phenylcarbonylamino, phenoxy or substituted phenoxy;

R⁹ represents cyano, —COR¹⁰, —CO₂R¹⁰ or —S(O)_(m)R¹¹;

R¹⁰ represents hydrogen or straight- or branched-chain alkyl groupcontaining up to six carbon atoms;

R¹¹ represents C₁₋₆ alkyl, C₁₋₆ haloalkyl, C₁₋₆ cyanoalkyl, C₃₋₈cycloalkyl optionally substituted with halogen, cyano or C₁₋₄ alkyl; orphenyl optionally substituted with one to three of the same or differenthalogen, nitro, cyano, C₁₋₄ haloalkyl, C₁₋₄ alkyl, C₁₋₄ alkoxy or—S(O)_(m)R¹²;

R¹² represents C₁₋₄ alkyl;

each Q independently represents C₁₋₄ alkyl or —CO₂R¹³ wherein R¹³ isC₁₋₄ alkyl;

-   m is zero, one or two;-   n is zero or an integer from one to four;-   r is one, two or three; and-   p is zero or an integer from one to six.

Suitably, X is chloro, bromo, nitro, cyano, C₁₋₄ alkyl, —CF₃,—S(O)_(m)R⁵, or —OR⁵; each Z is independently chloro, bromo, nitro,cyano, C₁₋₄ alkyl, —CF₃, —OR⁵, —OS(O)_(m)R⁹ or —S(O)_(m)R⁹; n is one ortwo; and p is zero.

Preferably, the 2-(substituted benzoyl)-1,3-cyclohexanedione of formula(II) is selected from the group consisting of2-(2′-nitro-4′-methylsulphonylbenzoyl)-1,3-cyclohexanedione,2-(2′-nitro-4′-methylsulphonyloxybenzoyl)-1,3-cyclohexanedione,2-(2′-chloro-4′-methylsulphonylbenzoyl)-1,3-cyclohexanedione,4,4-dimethyl-2-(4-methanesulphonyl-2-nitrobenzoyl)-1,3cyclohexanedione,2-(2-chloro-3-ethoxy-4-methanesulphonylbenzoyl)-5-methyl-1,3-cyclohexanedioneand2-(2-chloro-3-ethoxy-4-ethanesulphonylbenzoyl)-5-methyl-1,3-cyclohexanedione;most preferably is 2-(2′-nitro-4′-methylsulphonylbenzoyl)-1,3-cyclohexanedione.

Suitably, the concentration of the 2-(substitutedbenzoyl)-1,3-cyclohexanedione in the suspoemulsion formulation of thepresent invention is from 10 to 100 g/l, more suitably 25 to 60 g/l.

Examples of suitable stabilizing metal salts that may be used includecalcium, beryllium, barium, titanium, magnesium, manganese, zinc, iron,cobalt, nickel and copper salts; most suitable are magnesium, manganese,zinc, iron, cobalt, nickel and copper salts; especially preferred is acopper salt, for example copper hydroxide. Suitably, the concentrationof stabilizing metal salts in the suspoemulsion formulation of theinvention is from 0.01 to 4.0%, and preferably from 0.02 to 1.5%.

In a further aspect of the invention, there is provided a method forcontrolling the growth of undesirable vegetation such as weeds, whichmay be present around the locus of a desired plant species (which may ormay not exhibit resistance, either by natural means or by geneticmodification, to one or more herbicides), e.g. a crop such as corn,which comprises applying the formulation of the invention to the locusof such undesirable vegetation. Alternatively, in a further aspect ofthe invention, there is provided the use of the formulation of theinvention for the control of undesirable vegetation. Examples ofundesirable vegetation include, but are not limited to, velvetleaf,redroot pigweed, common water hemp, Palmer amaranth, ivyleaf morningglory, prickly sida, giant ragweed, common ragweed, common cocklebur,Eastern black nightshade, common lambsquarters, Pennsylvania smartweed,common sunflower, jimsonweed, hemp sesbania, toothed spurge, commonpurslane, large crabgrass, yellow foxtail and kochia. The weeds may ormay not demonstrate resistance (either naturally or geneticallymodification) to one or more herbicides. The suspoemulsion formulationmay be applied pre-emergence or post-emergence of the crop. Preferably,the formulation is applied pre-emergent. The formulation may be appliedby air or on the ground by known techniques, such as hydraulic nozzlespray.

One advantage of the suspoemulsion formulation of the present inventionis that, under the majority of conditions, season-long control of weedsis obtained by just one application of the formulation.

The present invention will now be described by way of example only.

EXAMPLE 1

1.1 Preparation of Premixes

1.1.1 Preparation of S-metolachlor EW % wt S-metolachlor 66.67 Aherbicidal antidote such as benoxacor 3.33 A polymer such as polystyrene4.18 A block copolymer such as Pluronic P65 2.13 Silicone antifoamingagent 0.18 Water 23.51

The polystyrene and benoxacor are dissolved in the s-Metolachlor.

The Pluronic P65 is dissolved in the aqueous phase and the antifoam isadded. The two are combined in such a way as to form an emulsifiedorganic phase with a particle size of 1-40 microns.

1.1.2 Preparation of Mesotrione Millbase % wt Mesotrione 35.00 Anon-ionic surfactant such as Tristyryl phenol with 2.89 16 moles of EOAcetic acid (56%) 11.01 Copper hydroxide (100%) 3.50 Siliconeantifoaming agent 0.10 Xanthan gum 0.10 Water 47.40

Mix together the water, acetic acid and copper hydroxide. Add themesotrione. The non-ionic surfactant, antifoaming agent, and xanthan gumare added and mixed until uniform. Mill until the median particle sizeis 1-6 microns.

1.2 Preparation of Final Product % wt S-Metolachlor EW 55.20 Mesotrionemillbase 10.50 Ethylene glycol 3.00 A non-ionic surfactant such as aC₉-C₁₁ 6.00 alkylpolyglycoside A block copolymer such as a butyl PO/EOsurfactant 5.00 Xanthan gum 0.16 A preservative such asbenzoisothiazolinone 0.15 Water rest

Blend together the s-Metolachlor EW, propylene glycol, the non-ionicsurfactant, the block copolymer and some of the water. Add themesotrione millbase and blend. Add the xanthan gum and preservative andblend until uniform. Assay and trim with water if needed.

EXAMPLE 2

2.1 Preparation of Premixes

2.1.1 Preparation of S-metolachlor EW % wt S-metolachlor 66.67 Aherbicidal antidote such as benoxacor 3.33 A polymer such as polystyrene3.68 A block copolymer such as Pluronic F108 1.00 Silicone antifoamingagent 0.18 Water 25.14

The polystyrene and benoxacor are dissolved in the s-Metolachlor.

The Pluronic F108 is dissolved in the aqueous phase and the antifoam isadded. The two are combined in such a way as to form an emulsifiedorganic phase with a particle size of 1-40 microns.

2.1.2 Preparation of Mesotrione Millbase % wt Mesotrione 35.00 Anon-ionic surfactant such as Tristyryl phenol with 3.50 25 moles of EOAcetic acid (56%) 11.01 Copper hydroxide (100%) 5.00 Siliconeantifoaming agent 0.10 Xanthan gum 0.10 Water 45.29

Mix together the water, acetic acid and copper hydroxide. Add themesotrione. The non-ionic surfactant, antifoaming agent, and xanthan gumare added and mixed until uniform. Mill until the median particle sizeis 1-6 microns.

2.2 Preparation of Final Product % wt S-Metolachlor EW 55.20 Mesotrionemillbase 10.50 Propylene glycol 3.00 A non-ionic surfactant such as aC₉-C₁₁ 5.00 alkylpolyglycoside A block copolymer such as a butyl PO/EOsurfactant 6.00 Xanthan gum 0.16 A preservative such asbenzoisothiazolinone 0.15 Water rest

Blend together the s-Metolachlor EW, propylene glycol, the non-ionicsurfactant, the block copolymer and some of the water. Add themesotrione millbase and blend. Add the xanthan gum and preservative andblend until uniform. Assay and trim with water if needed.

EXAMPLE 3

3.1 Preparation of Premixes

3.1.1 Preparation of S-metolachlor EW % wt S-metolachlor 66.67 Aherbicidal antidote such as benoxacor 3.33 A polymer such as polystyrene2.12 A block copolymer such as Pluronic F68 1.50 Silicone antifoamingagent 0.18 Water 26.20

The polystyrene and benoxacor are dissolved in the s-Metolachlor.

The Pluronic F68 is dissolved in the aqueous phase and the antifoam isadded. The two are combined in such a way as to form an emulsifiedorganic phase with a particle size of 1-40 microns.

3.1.2 Preparation of Mesotrione Millbase % wt Mesotrione 35.00 Anon-ionic surfactant such as Tristyryl phenol with 2.89 40 moles of EOAcetic acid (56%) 11.01 Copper hydroxide (100%) 5.00 Siliconeantifoaming agent 0.10 Xanthan gum 0.10 Water 45.90

Mix together the water, acetic acid and copper hydroxide. Add themesotrione. The non-ionic surfactant, antifoaming agent, and xanthan gumare added and mixed until uniform. Mill until the median particle sizeis 1-6 microns.

3.2 Preparation of Final Product % wt S-Metolachlor EW 55.20 Mesotrionemillbase 10.50 Glycerin 3.00 A non-ionic surfactant such as a C₉-C₁₁7.00 alkylpolyglycoside A block copolymer such as a butyl PO/EOsurfactant 3.00 Xanthan gum 0.16 A preservative such asbenzoisothiazolinone 0.15 Water rest

Blend together the s-Metolachlor EW, propylene glycol, the non-ionicsurfactant, the block copolymer and some of the water. Add themesotrione millbase and blend. Add the xanthan gum and preservative andblend until uniform. Assay and trim with water if needed.

EXAMPLE 4

4.1 Preparation of Premixes

4.1.1 s-Metolachlor EW (see 3.1.1)

4.1.2 Atrazine Millbase % wt Atrazine Technical (100%) 57.80 A non-ionicsurfactant such as an alkyl ethoxylate with 0.58 4 to 8 moles of EO AnEO/PO/EO block copolymer such as Pluronic P38 1.56 Glycerine 4.50Silicone antifoaming agent 0.12 Xanthan gum 0.05 A preservative such asbenzoisothiazolinone 0.05 Water rest

Mix together the surfactants, ethylene glycol and water until uniform.

Add antifoaming agent and Atrazine and mix. Grind slurry to a particlesize of 95% less than 17 microns. Add the xanthan gum and preservativeand mix until homogeneous.

4.1.3 Preparation of Mesotrione Millbase (see 3.1.2)

4.2 Preparation of Final Formulation % wt s-Metolachlor EW 44.1 Glycerin4.00 A non-ionic surfactant such as a C₉-C₁₁ 4.50 alkylpolyglycoside Ablock copolymer such as a butyl PO/EO surfactant 4.50 MesotrioneMillbase 8.4 Atrazine Basemix 19.0 Xanthan gum 0.9 A preservative suchas Benzoisothiazolinone 0.9 Water rest

Blend together the s-Metolachlor EW, water, propylene glycol andsurfactants until uniform. Add the mesotrione millbase and mix. Add theAtrazine Basemix followed by the xanthan gum and preservative and mixuntil uniform.

EXAMPLE 5

5.1 Preparation of Premixes

5.1.1 Preparation of S-metolachlor EW (see 2.1.1)

5.1.2 Atrazine Millbase % wt Atrazine Technical (100%) 57.80 A non-ionicsurfactant such as an alkyl ethoxylate with 4 to 8 1.15 moles of EO AnEO/PO/EO block copolymer such as 0.70 Pluronic P65 Ethylene Glycol 3.00Silicone antifoaming agent 0.12 Xanthan gum 0.05 A preservative such asbenzoisothiazolinone 0.05 Water rest

Mix together the surfactants, ethylene glycol and water until uniform.Add antifoaming agent and Atrazine and mix. Grind slurry to a particlesize of 95% less than 17 microns. Add the xanthan gum and preservativeand mix until homogeneous.

5.1.3 Preparation of Mesotrione Millbase (see 2.1.2)

5.2 Preparation of Final Formulation % wt % wt s-Metolachlor EW 44.1Propylene glycol 5.00 A non-ionic surfactant such as a C₉-C₁₁ 4.00alkylpolyglycoside A block copolymer such as a butyl PO/EO surfactant5.00 Mesotrione Millbase 8.4 Atrazine Basemix 19.0 Xanthan gum 0.9 Apreservative such as Benzoisothiazolinone 0.9 Water rest

Blend together the s-Metolachlor EW, water, propylene glycol andsurfactants until uniform. Add the mesotrione millbase and mix. Add theAtrazine Basemix followed by the xanthan gum and preservative and mixuntil uniform.

EXAMPLE 6

6.1 Preparation of Premixes

6.1.1 s-Metolachlor EW (see 3.1.1)

6.1.2 Atrazine Millbase % wt Atrazine Technical (100%) 57.80 A non-ionicsurfactant such as an alkyl ethoxylate with 4 to 8 1.69 moles of EO AnEO/PO/EO block copolymer such as Pluronic P38 0.40 Ethylene Glycol 3.00Silicone antifoaming agent 0.12 Xanthan gum 0.05 A preservative such asbenzoisothiazolinone 0.05 Water rest

Mix together the surfactants, ethylene glycol and water until uniform.

Add antifoaming agent and Atrazine and mix. Grind slurry to a particlesize of 95% less than 17 microns. Add the xanthan gum and preservativeand mix until homogeneous.

6.1.3. Preparation of Mesotrione Millbase (see 1.1.2)

6.2 Preparation of Final Formulation % wt s-Metolachlor EW 44.1 Glycerin5.00 A non-ionic surfactant such as a C₉-C₁₁ 3.00 alkylpolyglycoside Ablock copolymer such as a butyl PO/EO surfactant 6.00 MesotrioneMillbase 8.4 Atrazine Basemix 19.0 Xanthan gum 0.9 A preservative suchas Benzoisothiazolinone 0.9 Water rest

Blend together the sMetolachlor EW, water, propylene glycol andsurfactants until uniform. Add the mesotrione millbase and mix. Add theAtrazine Basemix followed by the xanthan gum and preservative and mixuntil uniform.

EXAMPLE 7

7.1 Preparation of Premixes

7.1.1 Metolachlor EW % wt Metolachlor 66.67 A herbicidal antidote suchas benoxacor 3.33 A polymer such as polystyrene 4.18 A block copolymersuch as Pluronic F108 1.87 Silicone antifoaming agent 0.18 Water 23.77

The polystyrene and benoxacor are dissolved in the Metolachlor.

The Pluronic F108 is dissolved in the aqueous phase and the antifoam isadded. The two are combined in such a way as to form an emulsifiedorganic phase with a particle size of 1-40 microns.

7.1.2 Atrazine Millbase (see 6.1.2)

7.1.3 Preparation of Mesotrione Millbase (see 1.1.2)

7.2 Preparation of Final Formulation % wt Metolachlor EW 44.1 Glycerin5.00 A non-ionic surfactant such as a C₉-C₁₁ 3.00 alkylpolyglycoside Ablock copolymer such as a butyl PO/EO surfactant 6.00 MesotrioneMillbase 8.4 Atrazine Basemix 19.0 Xanthan gum 0.9 A preservative suchas Benzoisothiazolinone 0.9 Water rest

Blend together the Metolachlor EW, water, propylene glycol andsurfactants until uniform. Add the mesotrione millbase and mix. Add theAtrazine Basemix followed by the xanthan gum and preservative and mixuntil uniform.

1. A suspoemulsion formulation comprising: (a) a continuous phasecomprising (i) one or more block co-polymers, and (ii) one or morenon-ionic surfactants; (b) a dispersed emulsion phase comprising (i) achloroacetamide, and (ii) a polymeric stabiliser; and (c) a dispersedsolid phase comprising (i) a 2-(substitutedbenzoyl)-1,3-cyclohexanedione herbicide; and (ii) a stabilising metalsalt.
 2. A suspoemulsion formulation according to claim 1, which furthercomprises one or more additional active ingredients.
 3. A suspoemulsionformulation according to claim 2, wherein the additional activeingredient is a herbicide.
 4. A suspoemulsion formulation according toclaim 2, wherein the additional active ingredient is a safener orantidote compound.
 5. A suspoemulsion formulation according to claim 2,wherein the additional active ingredient comprises a herbicide and asafener or antidote compound.
 6. A suspoemulsion formulation accordingto claim 1, wherein the continuous phase is selected from the groupsconsisting of water, glycol or alcohol.
 7. A suspoemulsion formulationaccording to claim 6, wherein the continuous phase is water.
 8. Asuspoemulsion formulation according to claim 1, wherein thechloroacetamide is a compound of formula (I)

wherein R¹ is hydrogen, methyl or ethyl; R² is hydrogen or ethyl; R³ ishydrogen or methyl; and R⁴ is methyl, methoxy, methoxymethyl, ethoxy, orbutoxy.
 9. A suspoemulsion formulation according to claim 8, wherein thechloroacetamide is selected from the group consisting of metolachlor,acetochlor and alachlor.
 10. A suspoemulsion formulation according toclaim 9, wherein the chloroacetamide is s-metolachlor.
 11. Asuspoemulsion formulation according to claim 1, wherein the2-(substituted benzoyl)-1,3-cyclohexanedione compound is a compound offormula (II)

wherein X represents a halogen atom; a straight- or branched-chain alkylor alkoxy group containing up to six carbon atoms which is optionallysubstituted by one or more groups —OR⁵ or one or more halogen atoms; ora group selected from nitro, cyano, —CO₂R⁶, —S(O)_(m)R⁵, —O(CH₂)_(r)OR⁵,—COR⁶, —NR⁶R⁷, —SO₂NR⁶R⁷, —CONR⁶R⁷, —CSNR⁶R⁷ and —OSO₂R⁸; R⁵ representsa straight- or branched-chain alkyl group containing up to six carbonatoms which is optionally substituted by one or more halogen atoms; R⁶and R⁷ each independently represents a hydrogen atom; or a straight- orbranched-chain alkyl group containing up to six carbon atoms which isoptionally substituted by one or more halogen atoms; R⁸ represents astraight- or branched-chain alkyl, alkenyl or alkynyl group containingup to six carbon atoms optionally substituted by one or more halogenatoms; or a cycloalkyl group containing from three to six carbon atoms;each Z independently represents halo, nitro, cyano, S(O)_(m)R⁹,OS(O)_(m)R⁹, C₁₋₆ alkyl, C₁₋₆ alkoxy, C₁₋₆ haloalkyl, C₁₋₆ haloalkoxy,carboxy, C₁₋₆ alkylcarbonyloxy, C₁₋₆ alkoxycarbonyl, C₁₋₆ alkylcarbonyl,amino, C₁₋₆ alkylamino, C₁₋₆ dialkylamino having independently thestated number of carbon atoms in each alkyl group, C₁₋₆alkylcarbonylamino, C₁₋₆ alkoxycarbonylamino, C₁₋₆alkylaminocarbonylamino, C₁₋₆ dialkylaminocarbonylamino havingindependently the stated number of carbon atoms in each alkyl group,C₁₋₆ alkoxycarbonyloxy, C₁₋₆ alkylaminocarbonyloxy, C₁₋₆dialkylcarbonyloxy, phenylcarbonyl, substituted phenylcarbonyl,phenylcarbonyloxy, substituted phenylcarbonyloxy, phenylcarbonylamino,substituted phenylcarbonylamino, phenoxy or substituted phenoxy; R⁹represents cyano, —COR¹⁰, —CO₂R¹⁰ or —S(O)_(m)R¹¹; R¹⁰ representshydrogen or straight- or branched-chain alkyl group containing up to sixcarbon atoms; R¹¹ represents C₁₋₆ alkyl, C₁₋₆ haloalkyl, C₁₋₆cyanoalkyl, C₃₋₈ cycloalkyl optionally substituted with halogen, cyanoor C₁₋₄ alkyl; or phenyl optionally substituted with one to three of thesame or different halogen, nitro, cyano, C₁₋₄ haloalkyl, C₁₋₄ alkyl,C₁₋₄ alkoxy or —S(O)_(m)R¹²; R¹² represents C₁₋₄ alkyl; each Qindependently represents C₁₋₄ alkyl or —CO₂R¹³ wherein R¹³ is C₁₋₄alkyl; m is zero, one or two; n is zero or an integer from one to four;r is one, two or three; and p is zero or an integer from one to six. 12.A suspoemulsion formulation according to claim 11, wherein the2-(substituted benzoyl)-1,3-cyclohexanedione of formula (II) is selectedfrom the group consisting of2-(2′-nitro-4′-methylsulphonylbenzoyl)-1,3-cyclohexanedione,2-(2′-nitro-4′-methylsulphonyloxybenzoyl)-1,3-cyclohexanedione,2-(2′-chloro-4′-methylsulphonylbenzoyl)-1,3-cyclohexanedione,4,4-dimethyl-2-(4-methanesulphonyl-2-nitrobenzoyl)-1,3-cyclohexanedione,2-(2-chloro-3-ethoxy-4-methanesulphonylbenzoyl)-5-methyl-1,3-cyclohexanedioneand2-(2-chloro-3-ethoxy-4-ethanesulphonylbenzoyl)-5-methyl-1,3-cyclohexanedione.13. A suspoemulsion formulation according to claim 12, wherein the2-(substituted benzoyl)-1,3-cyclohexanedione is2-(2′-nitro-4′-methylsulphonylbenzoyl)-1,3-cyclohexanedione.
 14. Asuspoemulsion formulation according to claim 1, wherein the stabilizingmetal salt is selected from the group consisting of calcium, beryllium,barium, titanium, magnesium, zinc, iron, cobalt, nickel and coppersalts.
 15. A suspoemulsion formulation according to claim 14, whereinthe stabilizing metal salt is selected from the group consisting ofmagnesium, manganese, zinc, iron, cobalt, nickel and copper salts.
 16. Asuspoemulsion formulation according to claim 15, wherein the stabilizingmetal salt is a copper salt.
 17. A method for controlling the growth ofundesirable vegetation, said method comprising applying a formulation asclaimed in claim 1 to the locus of such vegetation.
 18. (canceled)